Automatic hydraulic elevator valve control



Au 26,1941. v. F. LOVEJOY AUTOMATIC I'IYDRAULIC ELEVATOR VALVE CONTROL Filed Nov. 13, 1957 3 Sheets-Sheet l 5g v I;

. INVENTOR Mmcenz i7 Love '0 @QZZW ATTORNEY.

2 1941- v. F. LOVEJOY 2,253,570

AUTOMATIC HYDRAULIC ELEVATORVALVE CONTROL Filed Nov. 13, 1937 3 Sheets-Sheet 3 INVENTOR. V/ncenz A Am e '0 BY MQUWVVW/Z/ 4 TORNEY.

Patented Aug. 26, 1941 UNITED STATES: PATENT-OFFICE AUTOMATIC HYDRAULIC ELEVATOR VALVE CON ROL Vincent F. Lovejoy, San Diego, Calif. Application November 13, 1937, Serial No. 174,499

Claims. (01. 121-,-38) V v as Fig. 2; Fig. 6 is a View taken along the line My invention relates to an automatic hydraulic elevator valve control, and the objects of my invention are:

First, to provide a novel control for a'hydraulic elevator valve which control is automatic in its operation;

Second, to provide a control for a hydraulic elevator valve which will automatically control the opening and the closing of said valve;

Third, to provide a control for a hydraulic elevator valve which will close said'valve in such a way as to avoid the formation of a hydraulichammer;

Fourth, to provide a control for a hydraulic elevator valve which control in cooperation with the hydraulic elevator valve, will automatically stop the elevator at any predetermined'level of elevation regardless of the amount of the load being carried by said elevator;

Fifth, to provide acontrol of this class which avoids the use of springs andthereby complies with safety laws or ordinances regulating the use and operation of elevators;

Sixth, to provide a control of this class which will stop the elevator either in its descent or ascent upon failure of electric power;

Seventh, to provide a hydraulic control for a hydraulic elevator valve; and r 1 Eighth, to provide on the whole a novelly constructed automatic hydraulic elevator valve control which is durable, efficient in its action, and which will not readily deteriorate or get out of order, all in proportion to its function.

With these and other objects in View as will appear hereinafter, my invention consists of certain'novel features of construction, combination,- and arrangement of par-ts and portions as will be hereinafter described in detail and particularly set forth in the appended claims, reference being had to the accompanying drawings and to the characters of reference thereon which form a part of this application in which:

Figure l is a sectional view taken along the line I-I of Fig. 6; Fig. 2 is a fragmentary view on a slightly enlarged scale over the scale of Fig. l with parts and portions broken away to facilitate the illustration and showing the cross head, the knuckle member, and the knuckle member trip member in detail; Fig. 3 is a fragmentary sectional view taken along the line 3--3 of Fig. l on an enlarged scale; Fig. 4 is a fragmentary sectional view taken through the line 4-4 of Fig; 2 and of the same scale as Fig.2; Fig. 5 is a fragmentary sectional view taken along the line 5-5 of 'Fig. 2 and is of the same scale B6 of Fig. 1 and isof the same scale as Fig. 1; Fig. '7 is a fragmentary sectional View taken along the line I-'I of Fig. 6 and is on an enlarged scale over the Fig. 6;: Fig. 8 is a sectional view taken along the line 88 of Fig. 1 and is on an enlarged scale over the Fig. 1; and Fig. 9 is a diagrammatic illustration of my automatic hydraulic elevator valve control and shows in particular the principle of its operation;

1 Similar characters of reference refer to similar parts and portions throughout the several views of the drawings:

Cylinder l,;piston rod 2, crosshead 3, crosshead guide 4, knuckle member 5, trip member 6, Valve gate lever I, mercury switch 8, mercury switch trip member 9, solenoids ID and II, solenoid plungers I2 and I3, valve I4, check valve I5,

pressure relief valve I6, pump I'I, electric motor I8, solenoid I9, connection panel 20 and casing 2I constitute the principal parts and portions of my novel-automatic hydraulic elevator valve control. e V

- For the elevator, which is not shown, to either rise or descend, the gate member G of the valve A, indicated in Figs. 1 and 9 of the drawings;

must be open. "This valve member A'is positioned between the cylinder of the hydraulic elevator and'the pump for'the hydraulic elevator. Neither the: cylinder nor the .pump just mentioned are shown. The pipe P communicates with the cylinder for the hydraulic elevator. The gate G of valve A is shown'closed in Fig. l'of the drawings. This gate member G pivots about the journal B in the body of the valve A. The gate G is either opened or closed by pivoting about the journal 13 by means of the valve gate lever I which lever is connected with said journal B. This lever 1 consists of the two arms'la and 'Ib, 1a being shorter than 1b. The arm lb carries the weight 'Ic which may be shifted along this arm 1b to any desired position and secured in that position by the bolt Id. The arm 1a is secured by its end to the end 3b of the link So of the crosshead 3, the end -3bof link 3a being secured within slot Fe in the end of arm Ia. I-Ience as the crosshead 3 moves along its guide member 4, thegate G of the valve A in pivoting'about its journal B is either opened or closed by the arm 1a of the gate leverT.

' The crosshead. guide 4 is secured to one face of the channel member C as shown best in Figs. 1 and 3'of the drawings. This channelmember C stands on one of its sides and is secured along one edge of the channel member D by means of the bolt E, nut H, and sleeve member F as shown best in Figs. 3 and 6 of the drawings. The crosshead 3 has in its lower side a groove 30 extending therethrough to conform to the rail portion 4a of the crosshead guide 4. Thus the crosshead 3 will be retained on this guide member 4, yet it will be free to slide therealong. The crosshead 3 is connected to the piston rod 2; one end of the rod extends through the crosshead and is retained therein by means of the nuts 21) and 20 as indicated best in Figs. 1 and 3 of the drawings. To the opposite ends of the piston rod 2 is secured the piston 2a, which piston reciprocates within the cylinder I. The cylinder I has the end cap members Ia and lb. The piston rod 2 extends through the cap Ia, and the end of pipe Id is secured in a concentric opening in the cap member lb to admit fluid to or discharge fluid from the cylinder I. These two cap members Ia and lb are secured upon the ends of the cylinder I by means of the bolts I c. Hydraulic fluid such as water is admitted to the cylinder I through the pipe Id. The hydraulic fluid is drawn from the reservoir R through pipe I'Id and pipe I1c into the centrifugal pump IT. This pump I1 is driven by an electric motor I8 through the shaft IBa, the flexible coupling member I8b, and shaft I la. Hydraulic fluid is discharged from the pump I! through pipe I 'Ib and passes through the check valve I5 into the pipes I5a and Id into the cylinder I. This hydraulic fluid, as it is pumped into the cylinder I, drives the piston 2a from the end of the cylinder I having the cap lb to the end of the cylinder having the cap Ic. As the piston 2a is thus moved, the crosshead member 3 also moves in the same direction because of its connection to the piston rod 2, and as this crosshead member 3 moves as hereinbefore described, the gate G of the valve A is' at the same time being opened because of the connection of the gate G with the arm Id of the valve gate lever I and the link member 3a of the crosshead 3. The piston 2a in the cylinder I will be driven to the end of the cylinder I having the cap Ia as hydraulic fluid is pumped into the cylinder I,

and, upon reaching this end, will remain there until the valve I4 opens permitting the water within the cylinder I to flow back to the reservoir R through the pipe Id, I4), He and I'Id. The valve I4 is controlled by the solenoid II. The solenoid II has the plunger I3, which plunger is connected to the lever I 4b of the valve I4 by means of the link I3a. This link I3a is pivotally connected by the pin I 30 and by the pin I3b between the plunger I3 and the lever I4b as shown best in Fig. '7 of the drawings. This lever I42: is in connection with the gate I4a of the valve I 4. Positioned over one end of this lever I 4b is the weight I40 which weight may be shifted therealong and secured in any position desired by means of the bolt I4d. In Fig. 7 of the drawings this gate I4a of the valve I4 is shown open. To close the valve the plunger I3 must be drawn up into the solenoid I I by means of the magnetic field created by an electric current flowing through the windings of this solenoid II. When the current ceases to flow through the windings of this solenoid II, the gate I 4a will open due to the dropping due to gravity, of both the plunger I3, the lever I41), and its weight I 40. When the gate I40, of the valve I4 thus opens, the fluid within the cylinder I is thus permitted to flow back to the reservoir R. The solenoid II is controlled from the elevator.

When the piston 2a has reached the end of the cylinder I having the cap I a, the motor I8 driving pump I I will stop, as will be described hereinafter. A pressure relief valve I6 is provided to return the hydraulic fluid to the reservoir R directly from pump I I. This valve I6 connects with the pump I! through pipes Ifia and Ilb and connects with the reservoir R through pipe I61) and I111. The check valve I5 prevents the hydraulic fluid within the cylinder I from returning through the pipe Hill, and this hydraulic fluid, once it has been pumped into the cylinder I, will not be returned therefrom until valve I4 opens. When this valve I4 does open, the hydraulic fluid within the cylinder I will be displaced therefrom by the piston 2a returning from the end of the cylinder I having cap member Ia to the end of the cylinder having cap member lb. The piston 2a will be returned to the end of the cylinder I having the cap Ib thus displacing hydraulic fluid within the cylinder I out through valve I4 back to reservoir R by the action of the weight Ic acting on the lever arm lb of the valve gate lever I, the lever arm Ia of this lever I acting on the crosshead 3, and the crosshead 3 acting on the piston 2a to the piston rod 2. It should be noted that as this hydraulic fluid is thus being discharged from the piston I, that the gate G of the valve A is being closed, and that this cannot happen until the gate I4a of the valve I4 opens and'further that the opening of the gate I4a of the valve I4 is controlled by the solenoid II which in turn is controlled through an electric circuit, not shown, used in connection with the elevator. When the gate G of the valve A does close, the elevator must necessarily come to a stop since when this gate G is closed the hydraulic fluid can neither be pumped to the cylinder of this elevator, nor can the hydraulic fluid be returned from the cylinder of the elevator, since to do so the fluid must pass through the pipe P and through the valve A past the gate G thereof.

The piston 2a on its discharge stroke along with the crosshead 3 and the gate G of the valve A, as said gate G is being closed by the action of the weight 10 and the lever 12), will be stopped at a predetermined point before the gate G is completely closed. The crosshead 3 in moving with the piston 2a on its discharge stroke along the guide 4 will be arrested by the knuckle member 5. This member 5 is pivotally secured to the face of the channel member C by the bolt 5a and rests upon stud 5i and set screw 5g, which set screw is secured to the crosshead guide 4, all as shown best in Figs. 2 and 4 of the drawings and to some extent in Fig. 5. This set screw 5g is provided with the adjustment nut 5h. The knuckle member 5 is provided with a bifurcated portion, which is composed of the arms 5b and 50 as indicated in Fig. 5, the one end of which bifurcated member is secured by the bolt 5a to the channel 0 and the bifurcated ends composed of the arms 51: and 5c of which is provided with the pin 5d extending therethrough and securing the member 5e between the arms 5b and 50 thereof. The member 5e has secured in its one end the bolt 5 This member 5 normally rests upon the head of the set screw 59 and the stud 52'. This stud 52' is secured to the guide member 4 as indicated best in Fig. 2 of the drawings. When this knuckle member 5 is resting upon the stud 5i and the set screw 59, a line drawn through the head of the bolt 5f, the center 01' the pin 5d and the center of the head of bolt 5a would be a straight line and would lie in a horizontal plane,

The crosshead 3, in moving with the piston 2a on its discharge stroke, will be arrested by the head of the bolt 5 of the knuckle member 5 coming into contact with the recess 3e and the shoulder 3 of the crosshead 3. This piston 2a as well as crosshead 3 and valve gate G will be thus stopped until the knuckle is tripped so as to permit the crosshead 3 along with the piston 2a and the gate G to complete its travel. The knuckle 5 will be tripped by the stud 6c of the trip member 6 lifting up against the under side of the bifurcated arms 51) and 50 as indicated in Figs. 2 and 5 of the drawings.

The trip member 8 is pivotally secured to the guide member 4 by the pin 6:1 as shown best in Figs. 2, 4, and 5 of the drawings. This trip member 6 has the arm 6a, to the upper end of which is pivotally secured the rod I20. of the solenoid plunger I2. The other arm 61) of this trip member 6 has secured to its end the weight 60. This trip member 6 also has the stud Be. The normal position for the trip member 6 is shown by dotted outline in Fig. 2 of the drawings. When in this position the knuckle member 5 is resting upon the stud 5i and upon the head of the set screw 59. This trip member 6 is held in this position by the magnetic field created by the solenoid I acting upon the solenoid plunger I2. This plunger I2 is connected with the lever I227 through the link I20 which lever is pivotally connected by its one end to the pin I20 against the side of the channel member C. Integral with the lever I2d is the lever I2b which in turn is connected by its one end to the rod IZa. The levers 12b and IZd; move as a unit about the pin I2c whenever the solenoid plunger I2 is moved, and in this fashion move the rod I200. As long as the solenoid I8 is energized, the plunger I2 will hold the trip member 6 in the position shown for it by dotted outline in Fig. 2 of the drawings. But when this solenoid II! is no longer energized, the plunger I2 may drop to the position shown for it in Fig. 1 of the drawings, thus allowing the tripmember 6 to shift to the position shown for it by solid outline in Figs. 1 and 2 of the drawings. The stop member 61 contacts arm 6a to prevent trip 6 from moving beyond the position shown for it by solid outline in Fig. 2 when plunger I2 drops. The

weight to on the lever 6b aids in shifting the trip member 6 when plunger I2 drops, and the trip member 6 in pivoting about the pin 80. will lift the knuckle member to the position shown for it by solid outline in Fig. 2 of the drawings by means of the stud fie. When the knuckle member 5 has been tripped to the position shown for it by solid outline in Fig. 2, the crosshead 3, the piston 2a and the gate G of the valve A may complete their travel, so that the gate G of the valve A may close completely and so that the piston 20. of the moment when the solenoid I9 will cease to be energized so that the knuckle member 5 may be broken, as hereinbefore described, is determined by a means not shown nor described in either the specification or the drawings, but occurs shortly before the moment the elevator is to stop in either its ascent or its descent.

The pump I1 and the motor I8 are not in operation when the gate G of the valve A is completely open. The motor I8 shown in Fig. 9 of the drawings is a three-phase motor, although a single phase motor could be used equally as well. The electrical energy is supplied to this motor I8 by the wires running through the conduit I80, there being three such wires. Two of these wires have the terminal members I! and I8e which make contact with the switch IQ?) of the solenoid plunger I9a of the solenoid I9. Hence, when this switch member I9b makes contact with the two terminals I8d and I86, electrical energy will be furnished to the motor I8, but this switch member I911 will make contact with the elements I8d and I8e only when the solenoid I9 is energized. When the solenoid winding I9 is no longer energized, the plunger I9a. along with the switch I9b' will fall away from the elements I80! and I86, thus interrupting the flow of electrical energy to the motor I8. In the circuit with the solenoid I9 is the mercury switch 8. One side of the solenoid I9 connects with the conductor I9e, the other side of this solenoid I9 connects with the conductor I9c. This conductor I connects with the mercury switch 8, and another conductor I91 connects with the mercury switch 8 as indicated in Figs. 1 and 9 of the drawings. This mercury switch 8 is a glass tube 86 closed at its end containing the mercury 8b as shown best in Fig. 8 of the drawings. Two terminal members 88 extend part way into the tube 86 through one closed end thereof as indicated in Fig. 9 of the drawings. One terminal 80 connects with the conductor I90 and the other terminal 80 connects with the conductor I9f. The conductors I96 and I91 connect with a source of electrical energy which is not shown in the drawings. Hence, when the glass tube 86 of the mercury switch 8 is held in the position such that the mercury 81) will run down into the end supporting the elements 80, electrical connection between said elements 80 is thusly made. By rotating the position of this glass tube lie so that the mercury 8b will run away from the end having the elements 80, electrical connection is thusly broken. tube Be is supported within a clip 8d, which clip 8d is secured to the circular plate 8 and both the plate 8i and the glass tube 8e pivot about the pin 89. The pin 8g is secured to one side of the casing Sn and the glass tube 86, the clip 8d, the circular plate 8f are all positioned within this casing 8h. Between the circular plate 8 and the side of the casing Bit and secured by its one end to the pin 8g is the link member 81'. This link member 82' connects by its other end to one end of the rod 8a as shown best in Fig. l of the drawings. The end of the link 8i connecting with the rod 80. is positioned within the recess 87' which recess is cut in the periphery of the circular plate 8]. Thus when the rod 8a shifts laterally, the circular plate 8 rotates about the pivot 89. This rod 8a being connected to the mercury switch trip member is caused to Shift laterally thereby. This trip member 9 has the arm 9a which connects with the rod 8a and also has the bifurcated portion 91), and is secured upon the pin 90 to the side of the channel member C, all as shown best in Fig. l of the drawings. The trip member 9 is caused to shift by the stud 370 of the crosshead member 3 contacting either of the arms of the bifurcated portion 917. For the position shown for the switch in Figs. 1, 8, and 9 of the drawings, the motor I8 is running and will continue to run and drive the pump I'l until the trip member 9 is shifted by the stud 37s of the crosshead 3 causing the mercury switch 8 to rotate to a position where the mercury 80 will run away from the elements 80 in the glass tube 86, thus breaking the circuit for the solenoid I9 and consequently allowing the switch I92) to move away from the contact elements I8d and I8e.

The glass The rod 8k is secured by its-one end to the circular plate 8] near the periphery of said circular plate. The other end of the rod 870 extends through the slot 8p in the casing 8 The spring 8m is secured over the rod 8k; between the upper edge of the casing 8h and the periphery of the circular plate 8 as shown best in Figs. 1 and 8 of the drawings. This spring 8m and the rod 8 serve to hold the circular plate 8 in its extreme positions as shown best in Fig. 1 of the drawings. However, a failure of the spring 3m would not render the apparatus inoperative inasmuch as the mercury switch 8 would still move in response to a movement of trip 9.

The solenoids IG and II are secured within the casing 2I, and this casing 2I is positioned across the end of the automatic hydraulic elevator valve control as shown best in Fig. 6 of the drawings. The casing ZI is provided with a panel 29, which panel 23 is of some non-conductive material such as bakelite and has secured through it a plurality of terminal members 20a. These terminal members connect with the mercury switch 8, with the solenoids It and II and with the electric motor I8.

The operation of my automatic hydraulic elevator valve control is substantially as follows:

When the elevator is not in use the gate G of the valve A is closed. When th elevator is called into use the gate G of the valve A must be opened, and this is accomplished by pumping hydraulic fluid into the cylinder I so as to force the piston 2a to travel from the end of the cylinder I having the cap member Ib to the end having the cap member Ia. As the piston 2a thus moves through its strokes, it carries with it the crosshead 3 because of its connection with the piston rod 2 and also causes the gate G of the valve A to pivot about the journal B thereof because of the connection of the crosshead 3 with the arm Ia of the valve gate lever I and the crosshead link 3a. The pump I! and the motor I8 which drives this pump are called into operation when the solenoid I9 is energized, thus causing the switch I9b to make contact with the elements ISd and I3e, thus furnishing electrical energy to the mo tor I8. At this time the mercury switch 8 is in a position such that the mercury 8b in the glass tube 86 makes contact between the elements 80,

which elements 80 connect with the conductors I90 and I9). The hydraulic fluid is pumped by the pump H from the reservoir R. through the pipe lid to the pipe IIc to the pump I! and from the pump I? to the check valve I through the pipe I?!) and Ida and from the check valve I5 to the cylinder I through the pipes I5a and Id. During all this time the valve I4 has remained closed. When the piston 2a reaches the end of the cylinder I, having the cap I a, the gate G of valve A will be open and the stud 370 of the crosshead 3 will contact one of the arms of the bifurcated portion 9b of the mercury switch trip member 9 causing the same to rotate the glass tube 8e of the mercury switch 8 to a position such that the mercury 82) in this tube 8e will run away from the end of the tube 8e having the element 80, thus breaking the electrical circuit to the solenoid I9. When this happens the switch ISb will move away from the contact member I8d and I8e thus cutting off the supply of electrical energy to the motor I8. In this manner the pump I1 is shut off automatically and remain shut off while gate G of valve A is open full until the mercury switch 8 is tripped back to its original position where the mercury 812 will again make contact between the element 80. This will not happen until after the piston 2a and the crosshead 3 start to return to their original positions; that is, until the piston 2a starts to move away from the end of the cylinder having the cap Iatowards the end of the cylinder having the cap lb, but the piston 2a cannot make this return stroke until the hydraulic fluid within the cylinder I is released therefrom, and this is accomplished by opening the valve I4. The gate I4a of this valve I4 is operated by the plunger I3 of the solenoid II and will open when the solenoid II ceases to be energized electrically. The lever I42; and the weight I 40 along with the weight of the plunger I3 acting on the lever I4b due to the action of gravity will cause this gate I4a of the valve I4 to open, and conversely when the solenoid I I is energized, the plunger I3 will be lifted up into this solenoid II so as to close the gate I4a of the valve I4. Hence, to open the valve I4 to permit the hydraulic fluid within the cylinder I to return to the reservoir R, the gate I4a of the valve I4 must be opened and this happens when the circuit for the solenoid II is broken. The time when this circuit is broken is a predetermined matter which depends upon the level of elevation where the elevator is to be stopped. The hydraulic fluid returns from the cylinder I through the pipe Id and I 4 through the valve I4 to the pipe I46 and I 'Ib and back to the reservoir R. As this fluid is being discharged from the cylinder I, the piston 2a and the crosshead 3 are being returned to their original positions by the action of the weight Is on the end of the lever arm 'Ib, and as this is happening, the gate G of the valve A is being closed; but before the crosshead 3 and the piston 2 are completely returned to their original position, the crosshead 3 is arrested by contacting the knuckle member 5. When this happens the crosshead 3 and the piston 2a cease moving, thus leaving the gate G of the Valve A still slightly open and permitting the elevator to slowly creep to the desired level. The valve I4 during this time remains open. The piston 2a and the crosshead 3 may not complete their return stroke until the knuckle member 5 is tripped by the stud 66 of the trip member 6. This trip member 6 is connected with the plunger I2 of the solenoid ID by means of the rod I2a, the levers I2?) and I2d and the link member I2e. This trip member 6 is normally held in the position shown for it by dotted outline in Fig. 2 of the drawings by the plunger I2 being drawn up into the solenoid I0, the plunger I2 being attracted by th magnetic field created by the electric current flowing through this solenoid III. This plunger I2 will remain in this position until the electric current ceases to flow through the solenoid II]. The electric current flowing through this solenoid I0 is cut off shortly before the elevator reaches its desired level of elevation. The time interval between the cutting 01f of the current flowing through the solenoid Ill and the complete closure of the gate G of the valve A so that the elevator comes to a complete stop is approximately one second, but this may be varied by shifting weight along arm 'Ib. When this electric current ceases to flow through the solenoid III, the plunger I2 will drop due to action of gravity. Also the trip member 6, because of the weights 60 on the lever arm 6b thereof, will pivot about the point 6d so that the stud 66 will lift up against the under side of the knuckle member 5, shifting the same to the position shown for it by solid outline in Fig. 2 of the drawings and thus permitting the crosshead 3 and the piston 2a to complete their return stroke and also permitting the gate G of the valve A to close completely. In this manner the formation of a hydraulic hammer is avoided and also the operation of the elevator is greatly improved by the elimination of any sudden stoppage. Furthermore, in this manner the elevator can be automatically stopped at any predetermined elevation desired in an automatic manner and entirely independent of the loading on said elevator.

It should be noted that in the event the source of electrical energy to the motor l8 and to the solenoids In, H, and I9 should fail, the elevator will stop immediately, since both the plungers l2 and l3 of the solenoids I and II respectively would be permitted to drop, thus opening the valve l 4 and also tripping the knuckle 5 as hereinbefore described.

Though I have shown and described a particular construction, combination, and arrangement of parts and portions, I do not wish to be limited to this particular construction, combination, and arrangement, but desire to include in the scope of my invention the construction, combination, and arrangement substantially as set forth in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In an automatic hydraulic elevator valve control of the class described, the combination of a cylinder, a piston reciprocally mounted therein, a crosshead member in connection with said piston, guide means in connection with said crosshead member, a means to stop said crosshead member in its movement at a predetermined point and a trip means for said crosshead member stop means.

2. In an automatic hydraulic elevator valve control of the class described, the combination of a cylinder, a piston reciprocally mounted therein, a piston rod connected with said piston, a crosshead secured to said piston rod, a guide member supporting said crosshead, a link member connected to said crosshead, a lever pivotally and adjustably connected with said link member, a Weight adjustably mounted on said lever and a knuckle member connected with said crosshead arranged to stop said crosshead on its return stroke.

3. In an automatic hydraulic elevator valve control of the class described, the combination of a cylinder, a piston reciprocally mounted therein, a piston rod connected with said piston, a crosshead secured to said piston rod, a guide member supporting said crosshead, a link member connected to said crosshead, a lever pivotally and adjustab-ly connected with said link member, a weight adjustably mounted on said lever, a knuckle member connected with said crosshead arranged to stop said crosshead on its return stroke, and a trip member positioned to engage said knuckle member and trip the same.

4. In an automatic hydraulic elevator valve control of the class described, the combination of a cylinder, a piston reciprocally mounted therein, a piston rod connected with said piston, a crosshead secured to said piston rod, a guide member supporting said crosshead, a link member connected to said crosshead, a lever pivotally and adjustably connected with said link member, a weight adjustably mounted on said lever, a knuckle member connected with said crosshead arranged Ito stop said crosshead on its return stroke, a trip member positioned to engage said knuckle member and trip the same, and a solenoid provided with a plunger reciprocally mounted therein in connection with said trip member.

5. In an automatic hydraulic elevator Valve control of the class described, the combination of a cylinder, a piston reciprocally mounted therein, a piston rod connected with said piston, a crosshead secured to said piston rod, a guide member supporting said crosshead, a link member connected to said crosshead, a lever pivotally and adjustably connected with said link member, a weight adjustably mounted on said lever, a knuckle member connected with said crosshead arranged to stop said crosshead on its return stroke, a trip member positioned to engage said knuckle member and trip the same, a solenoid provided with a plunger reciprocally mounted therein in connection with said trip member, the solenoid operated by its magnetic field to hold its plunger within its core and to hold said trip member out of engagement with said knuckle member for a predetermined time.

I C T LO E-J 

